Omron CPM2A / CPM2AH Series Compact PLC

Description

⚠️ Critical: CPM2AH-40CDR-A is NOT 24V DC!​ Despite some distributor listings incorrectly stating “24V DC” , the authoritative Omron CPM2AH series table and product parameter pages confirm: CPM2AH-40CDR-A = AC power supply (AC100–240V, allowable AC85–264V), 40 I/O points (24 in + 16 relay out), relay output 2.1A/point. The “D” suffix (not present here — this is “A”) would indicate DC power. Your unit is -A = AC power. (Note: Some web listings for CPM2AH-40CDR-A show 24V DC — this is an error; trust the Omron official CPM2AH series table and the “-A” suffix convention. If your application requires 24V DC power, you need CPM2A-40CDR-D​ or CPM2AH-40CDR-D, NOT this -A model.)

💡 CPM2A vs CPM2AH — what’s the difference?

• CPM2A​ = original compact micro-PLC (4K program, 2K data memory, 0.64µs/instruction)
• CPM2AH​ = enhanced​ version — 31.2K program capacity, 6K data memory (+18K expanded), built-in 1-axis 100kHz pulse output, 4-axis 100kHz high-speed counter, 2-point analog output (6000 resolution), supports temperature module expansion (TS003)
• Both share the same physical footprint​ (90mm wide) and terminal layout​ — CPM2AH is a drop-in upgrade for CPM2A with more memory and features.
• The -S variant​ (CPM2AH-S40CDR-A) adds CompoBus/S master​ functionality (max 356 I/O: 100 local + 256 bus) — your CPM2AH-40CDR-A (without -S) does NOT have CompoBus/S master, just the standard features.

• CPM2A​ or CPM2AH​ = series
• 20/30/40/60​ = total I/O points
• C​ = CPU unit
• D​ = DC input type
• R​ = Relay output
• A​ = AC power supply (100–240V)
• D​ (at end) = DC power supply (24V) — note the two “D”s: the first is “DC input”, the last is “DC power”; in “CDR-D” the middle D=DC input, last D=24V DC power
• → CPM2A-60CDR-D​ = 60 I/O, DC input, Relay output, DC 24V power​
• → CPM2A-60CDR-A​ = 60 I/O, DC input, Relay output, AC power​
• → CPM2AH-40CDR-A​ = CPM2AH enhanced, 40 I/O, DC input, Relay output, AC power​

Technical Specifications Comparison

⚠️ Relay output limitation: ALL THREE units are relay output​ type. This means:

• NO high-speed pulse output​ — pulse output (10kHz/100kHz) is ONLY available on transistor output models (CPM2A-x0CDT-D / CPM2AH-x0CDT-D). If your application needs to drive a stepper/servo directly → these relay units are NOT suitable; you need the transistor (-T/-T1) variant.
• Relay switching speed: max ~0.1–0.2 Hz mechanical; suitable for contactors, indicators, solenoid valves (non-high-cycle). For high-frequency cycling → use transistor output.
• Contact rating 2A (CPM2A) / 2.1A (CPM2AH)​ @ 250V AC — enough for small contactors, indicators, and low-power loads. For heavier loads → use interposing relay.

Selection Guidance — Which One Do You Need?

• You need 40 I/O points​ (24 in + 16 relay out)
• AC power (100–240V) is available in your cabinet
• You want enhanced features: 31.2K program (vs 4K), built-in analog output (2-pt), 100kHz pulse + 100kHz×4 HSC, temperature module expansion
• You’re upgrading from a CPM2A-40CDR-A and want more memory without changing footprint
• CompoBus/S is NOT required (otherwise choose CPM2AH-S40CDR-A)

• You need 60 I/O points​ (36 in + 24 relay out)
• Your cabinet has 24V DC​ (industrial control voltage), no AC power available
• 4K program capacity is sufficient (simple machine logic)
• Cost-sensitive (CPM2A standard is cheaper than CPM2AH)

• You need 60 I/O points​ (36 in + 24 relay out)
• AC power (100–240V) is available
• 4K program capacity is sufficient
• This is the most common 60-point relay unit​ in the field — easiest to find as spare

📌 Most common scenario: If you’re maintaining an existing machine and the nameplate says “CPM2A-60CDR-A” → order exactly that. If it says “CPM2A-60CDR-D” → order that (DC-powered version). Mixing them up will result in the PLC not powering on (applying 24V to an AC unit or 110V to a DC unit will damage it).

Warranty & After-Sales

• Factory new units: 12 months warranty
• Refurbished units: 3-6 months warranty (bench: apply correct power (AC or DC per model) → PWR LED green → connect CX-Programmer via RS-232C (C200HS-CN220-EU cable or CPM1-CIF01) → upload/download program → force inputs → observe relay outputs click → verify expansion bus communication)
• Technical support for:
  • AC vs DC power verification​ (CPM2AH-40CDR-A and CPM2A-60CDR-A = AC 100–240V; CPM2A-60CDR-D = DC 24V​ — applying wrong voltage destroys the unit instantly. We confirm your existing unit’s nameplate before shipping.)
  • CPM2A → CP1E migration​ (CPM2A is discontinued; Omron’s official replacement is CP1E​ — CP1E-NA20DR-D (AC) / CP1E-NE30DR-D (DC) etc. . However, CP1E is NOT 100% pin-compatible — rewiring and program conversion (via CX-Programmer import) required. If you want a true drop-in, stay with CPM2A/CPM2AH.)
  • CPM2AH vs CPM2A choice​ (CPM2AH gives 31.2K program vs 4K, built-in analog out, 100kHz HSC vs 20kHz, 100kHz pulse vs none on relay — if your program is hitting the 4K limit or you need high-speed functions, CPM2AH is worth the premium. Footprint is identical, wiring is identical.)
  • Relay vs Transistor​ (All three listed are relay — if you need to drive stepper/servo or high-frequency switching → CPM2A-60CDT-D (NPN) or CPM2A-60CDT1-D (PNP) for DC-powered; CPM2AH-40CDT-D for enhanced DC. Relay units CANNOT do pulse output.)
  • Expansion module selection​ (CPM1A-8ED/8ER/8ET for 8-pt expansion; CPM1A-20EDR/20EDT for 20-pt; CPM1A-MAD01/11 for analog I/O; CPM1A-TS101/102 for thermocouple/RTD; max 3 units → 120 I/O total )
  • Programming cable​ (RS-232C: C200HS-CN220-EU (2m) to PC COM port; modern PCs need USB-to-RS-232 adapter + CPM1-CIF01; or use CQM1-PRO01-E handheld programmer)
  • Backup battery​ (CPM2A-BAT01 — for retaining DM, HR, AR, counter values during power-off; not included, order separately if needed )
  • CompoBus/S option​ (If you need CompoBus/S master — CPM2AH-S40CDR-A is the correct model, NOT the plain CPM2AH-40CDR-A. The “S” is critical.)
• Optional: CPM2A-BAT01 backup battery, C200HS-CN220-EU RS-232C cable, CPM1-CIF01 DIN-mount RS-232 adapter, USB-to-RS-232 adapter, CX-Programmer software, expansion units (CPM1A-8ED/8ER/20EDR/MAD01/TS101), CP1E migration kit (if upgrading)

Delivery Time

• Standard delivery: 3-5 working days (stock NOS — CPM2A/CPM2AH still available via aftermarket)
• Express shipping available upon request
• Note: Lead time from Omron directly is discontinued — we maintain NOS inventory; popular models (CPM2A-60CDR-A) typically in stock; less common (CPM2AH-40CDR-A) may require 2-3 weeks

Why Choose Our Store

• Genuine Omron CPM2A/CPM2AH — not gray-market (relay contact material & RS-232C PHY & program memory integrity critical — clones fail in the field and can’t be programmed with CX-Programmer)
• Global supply network with competitive pricing on Omron CPM2A/CPM2AH full range (all I/O sizes, AC/DC, relay/transistor)
• Expertise in CPM2A system (AC vs DC power decode, CPM2AH vs CPM2A feature comparison, relay vs transistor selection, expansion module pairing, CX-Programmer first-connect, CPM2A→CP1E migration path, CompoBus/S master requirement)
• Comprehensive technical documentation (CPM2A/CPM2AH dimensional drawings, terminal layouts, expansion bus cable wiring, CX-Programmer connection guide, CPM2A→CP1E migration cross-reference)
• Responsive customer service and support

Applications

• Legacy Machine Maintenance / Spare Parts: CPM2A-60CDR-A is THE workhorse of 1990s–2000s Japanese/Asian machines (packaging, labeling, small press, conveyor). When the original PLC fails, a genuine replacement restores production in under 30 minutes. No rewiring, no reprogramming — your existing CPM2A program downloads straight in.
• AC-Powered 60-Point Relay Control (CPM2A-60CDR-A): Ideal for machines with 100–240V AC control cabinet power. 36 DI + 24 relay DO handles complete machine sequences — contactor coils, solenoid valves, pilot lamps, alarm horns. The built-in 20kHz high-speed counter handles encoder input for length measurement or speed monitoring without extra modules.
• DC-Powered 60-Point Relay Control (CPM2A-60CDR-D): For cabinets with only 24V DC control power (common in European/automotive applications). Same 60-point I/O capability, but draws from the 24V DC bus. Critical for mobile equipment, battery-powered systems, or cabinets where AC power is isolated.
• Enhanced 40-Point with Analog (CPM2AH-40CDR-A): When you need 40 I/O PLUS built-in analog output (2-pt, 6000 resolution) for simple analog control (speed command to inverter, proportional valve) without adding expansion modules. The 31.2K program capacity handles complex sequences (PID, PWM) that the standard CPM2A 4K memory can’t fit. 100kHz HSC + 100kHz pulse (if paired with transistor output variant) enables simple positioning.
• CompoBus/S Master Requirement: If your machine network uses CompoBus/S, you MUST use CPM2AH-S40CDR-A​ (the -S variant), NOT plain CPM2AH-40CDR-A. The -S adds the CompoBus/S master, expanding I/O to 356 points (100 local + 256 bus). Plain CPM2AH-40CDR-A does NOT support CompoBus/S master.
• Migrating CPM2A → CP1E: If your CPM2A is failing and you want a future-proof replacement, Omron’s official path is CP1E. We can help scope the migration: CP1E-N□0DR-D (DC) or CP1E-N□0DR-A (AC) — but note: CP1E is NOT pin-compatible​ with CPM2A. You’ll need to rewire the terminal block (CP1E uses Euro-style removable terminals vs CPM2A’s MIL connector), and convert the program via CX-Programmer (import CPM2A project → adjust I/O addresses → download to CP1E). Budget extra engineering time for this migration. If minimal downtime is critical, staying with CPM2A/CPM2AH as a like-for-like replacement is the pragmatic choice.